Convert an Earth Engine (EE) image in a raster object
Convert an ee$Image in a raster object
ee_as_raster( image, region = NULL, dsn = NULL, via = "drive", container = "rgee_backup", scale = NULL, maxPixels = 1e+09, lazy = FALSE, public = TRUE, add_metadata = TRUE, timePrefix = TRUE, quiet = FALSE, ... )
image |
ee$Image to be converted into a raster object. |
region |
EE Geometry (ee$Geometry$Polygon) which specifies the region
to export. CRS needs to be the same that the argument |
dsn |
Character. Output filename. If missing, a temporary file is created. |
via |
Character. Method to export the image. Two methods are implemented: "drive", "gcs". See details. |
container |
Character. Name of the folder ('drive') or bucket ('gcs') to be exported. |
scale |
Numeric. The resolution in meters per pixel. Defaults to the native resolution of the image. |
maxPixels |
Numeric. The maximum allowed number of pixels in the exported image. The task will fail if the exported region covers more pixels in the specified projection. Defaults to 100,000,000. |
lazy |
Logical. If TRUE, a |
public |
Logical. If TRUE, a public link to the image is created. |
add_metadata |
Add metadata to the stars_proxy object. See details. |
timePrefix |
Logical. Add current date and time ( |
quiet |
Logical. Suppress info message |
... |
Extra exporting argument. See ee_image_to_drive and ee_image_to_gcs. |
ee_as_raster supports the download of ee$Images
by two different options: "drive"
(Google Drive) and "gcs"
(
Google Cloud Storage). In both cases, ee_as_stars works as follow:
1. A task is started (i.e., ee$batch$Task$start()) to
move the ee$Image from Earth Engine to the intermediate container
specified in the argument via.
2. If the argument lazy is TRUE, the task is not be
monitored. This is useful to lunch several tasks simultaneously and
calls them later using ee_utils_future_value or
future::value. At the end of this step,
the ee$Image is stored on the path specified in the argument
dsn.
3. Finally, if the argument add_metadata is TRUE, a list
with the following elements are added to the stars-proxy object.
if via is "drive":
ee_id: Name of the Earth Engine task.
drive_name: Name of the Image in Google Drive.
drive_id: Id of the Image in Google Drive.
drive_download_link: Download link to the image.
if via is "gcs":
ee_id: Name of the Earth Engine task.
gcs_name: Name of the Image in Google Cloud Storage.
gcs_bucket: Name of the bucket.
gcs_fileFormat: Format of the image.
gcs_public_link: Download link to the image.
gcs_URI: gs:// link to the image.
Run raster@history@metadata to get the list.
For getting more information about exporting data from Earth Engine, take a look at the Google Earth Engine Guide - Export data.
A RasterStack object
Other image download functions:
ee_as_stars(),
ee_as_thumbnail(),
ee_imagecollection_to_local()
## Not run:
library(rgee)
ee_Initialize(drive = TRUE, gcs = TRUE)
ee_user_info()
# Define an image.
img <- ee$Image("LANDSAT/LC08/C01/T1_SR/LC08_038029_20180810")$
select(c("B4", "B3", "B2"))$
divide(10000)
# OPTIONAL display it using Map
Map$centerObject(eeObject = img)
Map$addLayer(eeObject = img, visParams = list(max = 0.4,gamma=0.1))
# Define an area of interest.
geometry <- ee$Geometry$Rectangle(
coords = c(-110.8, 44.6, -110.6, 44.7),
proj = "EPSG:4326",
geodesic = FALSE
)
## drive - Method 01
# Simple
img_02 <- ee_as_raster(
image = img,
region = geometry,
via = "drive"
)
# Lazy
img_02 <- ee_as_raster(
image = img,
region = geometry,
via = "drive",
lazy = TRUE
)
img_02_result <- img_02 %>% ee_utils_future_value()
img_02_result@history$metadata # metadata
## gcs - Method 02
# Simple
img_03 <- ee_as_raster(
image = img,
region = geometry,
container = "rgee_dev",
via = "gcs"
)
# Lazy
img_03 <- ee_as_raster(
image = img,
region = geometry,
container = "rgee_dev",
lazy = TRUE,
via = "gcs"
)
img_03_result <- img_03 %>% ee_utils_future_value()
img_03_result@history$metadata # metadata
# OPTIONAL: clean containers
ee_clean_container(name = "rgee_backup", type = "drive")
ee_clean_container(name = "rgee_dev", type = "gcs")
## End(Not run)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.